Area Calculator

Select a shape and enter dimensions to calculate its area.

Area
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Formula Used

How to Use This Calculator

Let's say you're laying sod in a rectangular garden that's 12 feet long and 8 feet wide. Select "Rectangle" from the shape dropdown, enter 12 for Length and 8 for Width, then click Calculate. The result shows 96 square feet — that's how much sod you need to buy. Now suppose you also have a circular flower bed with a radius of 3 feet. Switch to "Circle", enter 3 for Radius, and you get 28.27 square feet. The total sod and soil you need is about 124 square feet. For a triangular garden border with a base of 6 feet and height of 4 feet, the triangle mode gives you 12 square feet using the formula ½ × base × height. Each shape shows the formula used in the result, so you can see exactly how the area was derived.

About Area Calculator

The Area Calculator is a versatile tool for computing the area of eight common geometric shapes: circle, triangle, rectangle, square, trapezoid, parallelogram, ellipse, and sector. Simply select the shape you are working with and input the required dimensions — the calculator instantly returns the area along with the formula used. This tool is ideal for students learning geometry who need to verify homework, for DIY enthusiasts calculating materials for home projects such as flooring or paint coverage, and for professionals in construction, landscaping, or interior design who regularly need quick area estimates. Each shape uses its standard mathematical formula; for instance, a circle uses πr², a rectangle uses length × width, and a trapezoid uses ½(a + b) × h. By understanding which formula applies to which shape, users build a stronger intuition for spatial reasoning. Whether you are tiling a floor, planning a garden bed, or studying for an exam, this calculator removes the guesswork and delivers accurate results in seconds.

When to Use This Calculator

Home Renovation & Flooring: Need to buy hardwood flooring for a room that's 15 feet by 12 feet? That's 180 square feet. But what about a circular rug area or a trapezoidal bay window? This calculator handles irregular shapes too, so you don't over-order materials or come up short.

Landscaping & Gardening: Whether you're calculating how much mulch covers a rectangular bed, the area of a circular pond liner, or the sod needed for an elliptical lawn, each shape's formula is built in. A 10-foot diameter circular garden bed has an area of about 78.54 square feet using the circle mode.

Real Estate & Interior Design: When listing a property, you need accurate room dimensions. An L-shaped room can be broken into two rectangles. The sector mode is useful for calculating the floor area of curved archways or angled walls. Accurate area measurements直接影响 material costs and property valuations.

Frequently Asked Questions

How do I calculate the area of a room that's not a perfect rectangle?

Break the room into smaller shapes. For an L-shaped room, split it into two rectangles, calculate each area separately, then add them together. If you have a curved wall, approximate it as a sector. The calculator supports 8 shapes, so you can mix and match results for any irregular space.

How do I calculate area of an irregular shape?

For irregular shapes, break the shape into smaller standard geometric shapes (rectangles, triangles, circles, etc.), calculate each area separately, and sum them. For curves, approximate with sectors or ellipses. The calculator supports 8 shapes per calculation, so you may need multiple calculations for highly irregular shapes.

What units can I use for area calculation?

The calculator works with any consistent unit system. If you enter dimensions in meters, the area will be in square meters. Use feet for square feet, inches for square inches, etc. The tool does not perform unit conversion — it simply computes the area using the values and units you provide.

How do I convert between square feet and square meters?

To convert square feet to square meters, multiply by 0.092903. For example, 100 sq ft = 9.29 sq m. To convert square meters to square feet, multiply by 10.7639. For quick estimates, remember that 1 sq m is roughly 10.76 sq ft, and 1 sq ft is about 0.093 sq m.

Why does the formula differ for circles vs rectangles?

Different shapes have different geometric properties. A rectangle's area is length × width because it's composed of unit squares. A circle uses πr² because π relates the circumference to the radius, and integration shows the area is π times the radius squared. Each shape formula is derived from its unique geometry and symmetry.